如何将CSV文件加载到
System.Data.DataTable
中,使创建的dataTable基于CSV文件?常规的ADO.net功能是否允许这样做?我一直在使用 OleDb
提供程序。但是,如果您读入具有数字值但希望将它们视为文本的行,则会出现问题。不过,您可以通过创建一个 schema.ini
文件来解决这个问题。这是我使用的方法:
// using System.Data;
// using System.Data.OleDb;
// using System.Globalization;
// using System.IO;
static DataTable GetDataTableFromCsv(string path, bool isFirstRowHeader)
{
string header = isFirstRowHeader ? "Yes" : "No";
string pathOnly = Path.GetDirectoryName(path);
string fileName = Path.GetFileName(path);
string sql = @"SELECT * FROM [" + fileName + "]";
using(OleDbConnection connection = new OleDbConnection(
@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly +
";Extended Properties=\"Text;HDR=" + header + "\""))
using(OleDbCommand command = new OleDbCommand(sql, connection))
using(OleDbDataAdapter adapter = new OleDbDataAdapter(command))
{
DataTable dataTable = new DataTable();
dataTable.Locale = CultureInfo.CurrentCulture;
adapter.Fill(dataTable);
return dataTable;
}
}
嗨,它正在工作 100%
public static DataTable ConvertCSVtoDataTable(string strFilePath)
{
DataTable dt = new DataTable();
using (StreamReader sr = new StreamReader(strFilePath))
{
string[] headers = sr.ReadLine().Split(',');
foreach (string header in headers)
{
dt.Columns.Add(header);
}
while (!sr.EndOfStream)
{
string[] rows = sr.ReadLine().Split(',');
DataRow dr = dt.NewRow();
for (int i = 0; i < headers.Length; i++)
{
dr[i] = rows[i];
}
dt.Rows.Add(dr);
}
}
return dt;
}
CSV 图像
导入的数据表格
https://www.nuget.org/packages/CoreTechs.Common/
例子:
var csv = @"Name, Age
Ronnie, 30
Mark, 40
Ace, 50";
TextReader reader = new StringReader(csv);
var table = new DataTable();
using(var it = reader.ReadCsvWithHeader().GetEnumerator())
{
if (!it.MoveNext()) return;
foreach (var k in it.Current.Keys)
table.Columns.Add(k);
do
{
var row = table.NewRow();
foreach (var k in it.Current.Keys)
row[k] = it.Current[k];
table.Rows.Add(row);
} while (it.MoveNext());
}
我们过去一直使用Jet.OLEDB驱动程序,直到我们开始使用64位应用程序。微软没有发布也不会发布64位的Jet驱动程序。这里是一个简单的解决方案,它使用File.ReadAllLines和String.Split来读取和解析CSV文件,并手动加载一个DataTable。正如上面所提到的,它无法处理其中一个列值包含逗号的情况。我们主要用于读取自定义配置文件 - 使用CSV文件的好处是可以在Excel中编辑它们。
string CSVFilePathName = @"C:\test.csv";
string[] Lines = File.ReadAllLines(CSVFilePathName);
string[] Fields;
Fields = Lines[0].Split(new char[] { ',' });
int Cols = Fields.GetLength(0);
DataTable dt = new DataTable();
//1st row must be column names; force lower case to ensure matching later on.
for (int i = 0; i < Cols; i++)
dt.Columns.Add(Fields[i].ToLower(), typeof(string));
DataRow Row;
for (int i = 1; i < Lines.GetLength(0); i++)
{
Fields = Lines[i].Split(new char[] { ',' });
Row = dt.NewRow();
for (int f = 0; f < Cols; f++)
Row[f] = Fields[f];
dt.Rows.Add(Row);
}
您可以使用C#中的Microsoft.VisualBasic.FileIO.TextFieldParser dll来实现它。
static void Main()
{
string csv_file_path=@"C:\Users\Administrator\Desktop\test.csv";
DataTable csvData = GetDataTabletFromCSVFile(csv_file_path);
Console.WriteLine("Rows count:" + csvData.Rows.Count);
Console.ReadLine();
}
private static DataTable GetDataTabletFromCSVFile(string csv_file_path)
{
DataTable csvData = new DataTable();
try
{
using(TextFieldParser csvReader = new TextFieldParser(csv_file_path))
{
csvReader.SetDelimiters(new string[] { "," });
csvReader.HasFieldsEnclosedInQuotes = true;
string[] colFields = csvReader.ReadFields();
foreach (string column in colFields)
{
DataColumn datecolumn = new DataColumn(column);
datecolumn.AllowDBNull = true;
csvData.Columns.Add(datecolumn);
}
while (!csvReader.EndOfData)
{
string[] fieldData = csvReader.ReadFields();
//Making empty value as null
for (int i = 0; i < fieldData.Length; i++)
{
if (fieldData[i] == "")
{
fieldData[i] = null;
}
}
csvData.Rows.Add(fieldData);
}
}
}
catch (Exception ex)
{
}
return csvData;
}
这是我使用的代码,但您的应用程序必须在 .NET 3.5 版本上运行。
private void txtRead_Click(object sender, EventArgs e)
{
// var filename = @"d:\shiptest.txt";
openFileDialog1.InitialDirectory = "d:\\";
openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
DialogResult result = openFileDialog1.ShowDialog();
if (result == DialogResult.OK)
{
if (openFileDialog1.FileName != "")
{
var reader = ReadAsLines(openFileDialog1.FileName);
var data = new DataTable();
//this assume the first record is filled with the column names
var headers = reader.First().Split(',');
foreach (var header in headers)
{
data.Columns.Add(header);
}
var records = reader.Skip(1);
foreach (var record in records)
{
data.Rows.Add(record.Split(','));
}
dgList.DataSource = data;
}
}
}
static IEnumerable<string> ReadAsLines(string filename)
{
using (StreamReader reader = new StreamReader(filename))
while (!reader.EndOfStream)
yield return reader.ReadLine();
}
改编自ChuckBevitt先生
解决方案如下:
string CSVFilePathName = APP_PATH + "Facilities.csv";
string[] Lines = File.ReadAllLines(CSVFilePathName);
string[] Fields;
Fields = Lines[0].Split(new char[] { ',' });
int Cols = Fields.GetLength(0);
DataTable dt = new DataTable();
//1st row must be column names; force lower case to ensure matching later on.
for (int i = 0; i < Cols-1; i++)
dt.Columns.Add(Fields[i].ToLower(), typeof(string));
DataRow Row;
for (int i = 0; i < Lines.GetLength(0)-1; i++)
{
Fields = Lines[i].Split(new char[] { ',' });
Row = dt.NewRow();
for (int f = 0; f < Cols-1; f++)
Row[f] = Fields[f];
dt.Rows.Add(Row);
}
CommonEngine.CsvToDataTable(path, "ImportRecord", ',', true);
private static DataTable LoadCsvData(string refPath)
{
var cfg = new Configuration() { Delimiter = ",", HasHeaderRecord = true };
var result = new DataTable();
using (var sr = new StreamReader(refPath, Encoding.UTF8, false, 16384 * 2))
{
using (var rdr = new CsvReader(sr, cfg))
using (var dataRdr = new CsvDataReader(rdr))
{
result.Load(dataRdr);
}
}
return result;
}